Ionizing radiation is a type of high-energy radiation that has the potential to release electrons from atoms and molecules, creating ions that can break covalent bonds. This type of radiation can directly affect the structure of DNA by inducing DNA breaks, particularly double-stranded breaks (DSB). Additionally, it can generate reactive oxygen species (ROS) that oxidize proteins and lipids, as well as cause various types of DNA damage, such as the generation of abasic sites and single-stranded breaks (SSB). All of these changes can lead to cell death and mitotic insufficiency.
Radiation can also damage chromosomal DNA inside the cell nucleus, which can cause cancer. However, it is not known how this occurs or how many tumors are caused by radiation damage. There are two main ways that radiation can damage DNA inside living cells:1.